PHOTOS: Oldest "Human" Skeleton Refutes "Missing Link"

Editor's note: At the request of illustrator J.H. Matternes and Science/AAAS, we are removing the illustrations of Ardipithecus ramidus that were once featured here. The illustrations may be viewed in a scientific paper.

The Middle Awash study area, where the Ardipithecus bones were found, is on the Awash River about 140 miles (230 kilometers) from the Ethiopian capital of Addis Ababa.

It's part of the parched Afar rift valley, where the famous "Lucy" skeleton was found farther to the north.

The valley was formed by the wrenching apart of three massive sections of Earth's crust. Volcanoes, earthquakes, and erosion associated with the rifting have had the effect of first burying, and then much later disgorging to the surface, fossils formed millions of years before.